The present invention relates to a remote control system for selective load switching, and more particularly to an automatic warning or supervisory system which provides for operator supervision of proper operation of the system.
U.S. patent application Ser. No. 648,783, filed Jan. 13, 1976, Werner MEIER, now U.S. Pat. No. 4,085,403, assigned to the assignee of the present application, discloses a system in which a central station is provided from which loads can be selectively addressed. The central station and a plurality of loads are all connected to a bus system which includes a clock bus line, a power bus, a control bus, and a feedback or reply bus on which signals appear acknowledging that a certain command is acknowledged and has been executed. A cyclically operated counter is connected to the clock bus to provide cyclical counts. Switching or addressing pulses, corresponding to specific count numbers and occurring in synchronism with the clock pulses on the clock bus are used to address selected loads. The loads, each, have a receiver section in which a counter is provided, stepping in synchronism with the counter of the central station. A decoding circuit, specific for each discrete load, decodes coincidence between the pulses on a control bus and the specific count number associated with the load and, upon coincidence of the count number by the counter, the number assigned to the load, and a pulse on the control bus, the load is addressed to carry out a predetermined switching function. Acknowledgment of the switching function is then transmitted coincident with the control pulse on the reply or acknowledgment bus.
Pilot installations have shown that systems of this kind have excellent operating characteristics and are suitable for commercial application.
These systems are particularly applicable to control the connection of selectively addressed loads in automotive vehicles. Traffic safety places high requirements on the reliability of such systems.